Automatic draft-regulator and return-trap.



M. F. HUTCHISON. AUTOMATIC DRAFTIREGULATOR AND RETURN TRAP. APPLICATION FILED AUG.24. 1911.

1,261,030. Patented Apr. 2,1918.

3 SHEETSSHEET 1.

M. F. HUTCHIS ON. AUTOMATIC DRAFT REGULATOR AND RETURN TRAP.

APPLICATION FILED Aue.24. 1917.

Patented Apr. 2, 1918.

3 SHEETSSHEET 2- M. F. HUTCHlSON.

AUTOMATIC DRAFT REGULATOR AND RETURN TRAP. APPLICATION FILED AUG.24. I91].

1 $6 1,030. Patented Apr. 2, 1.91s.

.3 SHEETS-SHEET 3- MAURICE FRANK rin'roin'son, or Hermon, vrnemm.

An'roMArIo nRAFT nEGnLAron; AND RETURN-TRAP.

Patented Apiu'2, 191s.

lat-cast iiled'iiig iist 24, 1917'. Selma. 181519.

Ta ball whom it concrhq. n y, Be it known thatl, MA nIon FnAnK Ho'ronrson, a citizen ofjthe United States,

residing at Herndon, county of Fairfax,

and State of Virginia, have invented cei' tain new and useful Improvements in Automatic Draft Regulators and Return-Traps, of which'the following is a full, clear, and exact specification. 1

This invent-ionrelates to draft regulators u qma c lly. c t le y. t e ati plants to which they are attached and is especially designed for vaporheatlng systems. i

The invention also inclu desaii improved safety appliance for relieving excess pressure in emergencies V i v n One object of theinvention is to prevent the water or steambacking up from the boiler into the radiators in case of excessive pressure of vapor in the boiler due, for instance, to the ash pit door being left open.

Another object is to utilize the water of condensation from the radiators for operating the damper regulator.-

A further ob'ect is to v dispense with all cheek, thermostaticand float valves heretofore used in vapor heating systems and provide a 'devicewhich has 'no movable parts. in the returns from the radiators to the boiler.

Still another object is to provide means for adjusting the regulator .so that it will automatically operate the dampers at different predetermined pressures of the vapor in the system.

Theinvention will be first hereinafter described in connection with the accompanying drawings, which constitute a part of this specification, and then more specifically defined in the claims at the end of the description.

Inthe accompanying drawings, wherein similar reference characters are used to designate corresponding parts in. all the views: V M

.Figure 1 isa side elevation of the of avapor heating plant, showing my iniproved damper regulator attached;

Fig. 2 is a frontelevation of the same; .Fig. 3 is an enlarged detail sectional view thef ap re .s iversM.v T

Fig. 4: is an enlarged front elevation of bane-f the adjusting means for varying the pressure required to operate the dampers;

Fig. 5 is a diagrammatic view illustrating thearrangement of the system, and

Fig. 6 is an enlarged detail sectional view of a modifijed form of trap. v

The normal water linein the boiler A is indicated by a broken linena" in 1, and said line is extended acros snthe trap receiver B which is connected to the return inlet or the boiler bya pipe C, This fits into abored boss'D extending upwardly fromSthe bottom of the trap receiver (see Fig. 3). Obviously the water line in the pipe 0 or in the boss D, which is in effecta" Continuation of the pipe C, will be on the same level as the water line in the boiler. As a general proposition the water line in the boiler normally is, ator just below the top of said boss As shown in Figs. 1 to 5 the main portion of the trap receiver sur rounding the boss D is connected to the m: diators of the heating plant by: the return pipe E entering the bottomof said trapre-.

ceiver; The looped portion of said pipe E below the trap receiver constitutes the trap proper; However, it is not intended-to limit this invention to this particnlar form of trap as any trap, broadly speaking, may be utilized. A modified form of trap is shown in Fig. 6, wherein the downwardly extending portion of return pipe E below said trap receiver D is dispensed with and the upwardly extending portion of said return pipe E Fi 6, opens directlyinto the trap receiverB and ex tends to a point below the upper edge of the boss Equally as good results are obtainedby this form of trap as the trap arrangement shown in the other figures. The feed pipe from the boiler to the radiators has a branch pipe F leading to the top of the trap receiver.

From a point in the. pipe E abranch pipe G leads to a hollow globe or reservoir H,

there being'a flezrible section G in said pipeglobe H normally stands above the: water level in the trap receiver B, as seen: inEig. 1. An air ventpipe ortube J pier: erably flexible, leads from thetop ofsaid o ism e ervo r t h P p E a ap nt above: said water level in the trap receiver B. Said pipeE is also provided with a vent branch E arranged at a still higher level. .Said vent pipe E rises from a horizontal portion of the return pipe E, so that the proper return of the water of condensation is not affected, but in case the water backs up in said return pipe, as hereinafter explained, due to excessive pressure of the vapor on said water, said water in the vertical portion of the return pipe E and trap receiver B will be forced into the horizontal portions E of the return pipes and when all of said water has been forced into said horizontal portions of the return pipes E, the vapor following will escape through the vent pipe E, the water in the horizontal portions of said return pipe returning automatically and re-sealing the trap after the pressure falls, as will be obvious. The amount of water contained in the vertical portion of the return pipe E and trap receiver B is not sufficient to cause said water to reach the radiators and back up therein, but such water simply remains or lies in the horizontal. portions of the return pipe E until the pressure falls, and as stated, then returns automatically to re-seal the trap.

The reservoir H is adjustably connected to an intermediate part of a chain or other flexible connection K secured at one end to a direct draft damper L in the ash door,

, and at the other end to a check damper M in the flue N leading from the boiler to the chimney. This chain K is passed over sheaves P so that when moved in one direction it opens one damper and closes the other, and vice versa.

In operation, when the vapor or steam pressure rises above a predetermined point, water is forced up into the reservoir H. The trap receiver B and pipe E contain sufficient Water to fill said reservoir H and to maintain a predetermined pressure in the boiler. As soon as said reservoir starts to fill, the added weight of the water therein causes it to gradually lower or drop, overcoming the spring R which normally acts as a counterbalance for said reservoir and the parts attached thereto. By reason of the connection between said reservoir and chain K, when the reservoir drops the direct .draft damper L is closed and the check draft damper M opened, retarding combustion and obviously causing the pressure of vapor to be reduced. \Vhen such pressure has become reduced to the desired degree the water will run back from the reservoir H, whereupon the spring R will raise said reservoir to the position shown in the drawings, thereby opening the directdraft damper again and closing the check draft damper.

to the bottom of the portion of the trap receiver B surrounding the boss I). It is therefore, the water of condensation from the radiators that is used for this purpose. The pressure in the boiler is communicated to the trap receiver B by the branch pipe F and acts upon the surface of the water of condensation in said trap receiver to force vacuum in the reservoir when the water flows from the same back into the trap via the pipes G, G. The vent pipe E, in con junction with the trap also serves as a safety device, allowing the water in the vertical portion of the return pipe E and the trap receiver B to be forced past said vent pipe into horizontal portions of the return pipe E and the vapor following to escape through the Vent pipe in case the pressure in the boiler becomes too high, which might occur if the ash pit door was left open and the ordinary safety valve failed to operate. In such an emergency the water in the trap and in the vertical portions-of the return pipe E would be forced into the horizontal portions of the return pipe E by the pressure 7 of vapor entering the trap through pipe F without affecting the water in the boiler to' any appreciable extent inasmuch as the pressure on the surfaces of the water in the boiler and on the surface of the water in the boss D or pipe C is the same. The vapor following the water thus forced into the horizontal portions of the return pipe then escapes through vent pipe E to the atmos phere. As will be apparent from the diagrammatic view part of the water thus forced into the horizontal portions of the return pipes is forced into the horizontal portion to the left of the upwardly extending portion of the return pipe E and part of the water forced into the horizontal portion of the return pipe E beyond the connection of the vent pipe E with said horizontal portion E and to a point in said horizontal portion of said pipe between the vent pipe connection therewith and the radiators. Should all the water in the trap and return pipe E be forced out in this way, the vapor will follow and relieve the pressure in the boiler in an obvious manner. It will be observed that if it were not for the vent pipe E, excessive pressure in the boiler, under the conditions mentioned, would cause the water in the trap and return pipe E to back up in said return pipe and radiators. The return pipes it will be understood are of suf 

